DHCPv4 packet processing (Kea 1.8.0) Process Query on its Message Type Process Discover Process Request Process Release Process Decline Process Inform Receive query input Service Enabled Callout buffer4_receive hook Unpack query Classify query Callout pkt4_receive hook Check DROP class Avoid same client race in multi-threaded mode postpone processing or drop Callout leases4_committed hook Park Callout pkt4_send Send response Pack response Callout buffer4_send output Drop packet error service is enabled service is disabled CONTINUE SKIP DROP on error CONTINUE DROP query in DROP class queries from the same client possible race unknown message type on error on error on error on error on error CONTINUE DROP PARK unpark CONTINUE SKIP DROP CONTINUE DROP dashed arrow means asynchronous processing